Engine speed governing means



Jan. 8, 1963 T. F. CRAMER ENGINE SPEED GOVERNING MEANS Filed April 1, 1958 2 Sheets-Sheet l THOMAS F. CRAMER:

3,072,110 ENGINE SPEED GOVERNING MEANS Thomas F. Cramer, Warren, Mich, assiguor to Holley Carburetor tlornpany, Van Dylre, Mich, a corporation of Michigan Fiied Apr. 1, 1958, Ser. No. 725,751 11 Claims. (Cl. 1231ti3) The present invention relates generally to engine speed governing means, and more particularly to vacuum responsive governing means associated with the carbureting apparatus.

Present day velocity type engine governors are almost entirely dependent on the velocity of air flow through the engine air intake passage for the governor motivating force. The usual design incorporates a body portion having an induction passage and a throttle valve therein which is acted upon and urged in the closing direction by air flow against the resistance of spring means. Since in these designs the throttle must be presented to "the air flow in such a manner so as to ofier some restrictive effects thereto, the volumetric efficiency of the engine is affected. In addition to this, other undesirable effects are obtained, such as a tendency for the governor throttle valve to flutter, surge and hunt.

However, the most outstanding defect in all of these designs is poor regulation, or in other words, excessive spread between full load governed speed and no-load governed speed. This again, is due to the fact that regulation is dependent almost entirely on the incoming air impinging upon the governor throttle valve.

Accordingly, it is an object of the present invention to provide velocity-type engine speed governing means which are not in any way dependent on air flow as a motive force.

More specifically, it is an object of the present invention to provide non-surging governing means employing intake air flow as a sensing means and intake manifold vacuum as the motivating force.

Other objects and features of the invention will become apparent as the description proceeds, especially when taken in conjunction with the accompanying drawings, illustrating preferred embodiments of the invention, wherein:

FIGURE 1 is an elevational view in section illustrating generally the invention and surrounding structures.

FIGURE 2 is an enlarged sectional view of the governor mechanism, just prior to governing.

FIGURE 3 is the same View showing the details in the position occupied during governing.

FlGURE 4 is a View similar to FIGURES 2 and 3, with the parts in the position occupied at part throttle or idle condition.

Referring in greater detail to FIGURE 1, a carburetor having a body 12, a fuel bowl 14, and a nozzle to discharging into the induction passage 13 having a choke valve and throttle valve 2-2 therein, is shown mounted atop the governor 2 1- and communicating therethrough with the intake manifold 26 atop which is secured the said governor. A conduit 28 communicates between the intake manifold and a chamber within said governor hous- FIGURE 2 illustrates the governor assembly 24 which is substantially comprised of a body portion :2 having therein an induction passage 3% adapted to be controlled by a governor throttle valve 32 mounted on a shaft 34, and a housing 36 which when mounted on the body, secures between itself and said body, diaphragms 38 and 4%}. Power chamber 44, formed by diaphragm 4i] and housing 36, contains a spring adjustably mounted on a screw 52 normally biasing the diaphragm at to the left.

Chamber 44 has a restricted bleed port 53 connected to the air induction passage 3% at a port 53a between the sates ii att iii aerans ice 2 carburetor throttle valve 22 and the governor throttle valve 32. Connecting chamber 54 to the left of the diaphragm 40 is vented to the atmosphere by port 56.

A piston type valve 57 contained Within the valve chamber 46 and having spaced lands 53 and 59 defining therebetween a generally annular recess 69 formed about its diameter is suitably secured to diaphragm 38 through a rod 62. The chamber as to the right of piston valve 57 is vented to the atmosphere through port 64- and contains a spring 66 normally biasing the piston and diaphragm to the left.

An annular passage 68 is formed about the induction passage Si by a recess and ring-like structure 70 cooperates therewith and communicates with the air flow through said induction passage by means of a plurality of conduits 72, and with the control chamber 76 to the left of diaphragm 38 by means of port i i. A stop 77 limits movement of the valve 57 to the left.

An arm 78 rigidly secured to the throttle shaft 34 is operatively connected to one end of a rod so while the other end of said rod is suitably secured to diaphragm 4t Conduit 23 which leads from the intake manifold to housing 36 communicates with chamber 44 therein 5 through aligned ports 43 and 49 adapted to be controlled by the position of the piston valve land 59 and annular recess so therein. Atmospheric port 81 is controlled by valve land 58 and recess so in admitting atmospheric air to chamber 44 through aligned port 32.

Operation of Invention During engine operation at idle or with the carburetor throttle 22 in an intermediate (part throttle) position, governing is not necessary and hence the arrangement is such that under these conditions, the governor throttle 32 is in wide open position. At this time, the parts are in the position illustrated in FIGURE 4. Pressure at the conduits 72 is very low and may be a negative value. Spring 66 therefore forces valve 57 to the left. The stop 77 prevents the piston 57 from moving too far to the left. At this time, the atmospheric bleed ports 81 and 82 are aligned with annular passage 69 admitting atmospheric pressure to chamber 44, thereby raising pressure in the chamber.

When the carburetor throttle is at idle, pressure at the port 53:: and picloups 72 will be negative and this reduced pressure (partial vacuum) will be transmitted to chamber 4 through restriction 53. However, this vacuum is destroyed by the additional air bleed which is controlled by the piston valve 57.

When the engine is operating below governed speed with the carburetor throttle 22 wide open the parts are in the relative position illustrated in FIGURE 2 except that the piston valve 57 may be somewhat further to the left. At this time the pressure within the power chamber 44 is slightly below atmospheric, since the pressure at port 53a is below atmospheric. If however, the valve 57 is further to the left from the illustrated position it will be observed that the interior of the power chamber 44 may be connected to atmosphere through the ports 1%, 81 as seen in FIGURE 4.

Assuming an increase in speed, and with the carburetor throttle 22 wide open, the velocity of air flow through the induction passage 39 increases and hence the dynamic pressure as sensed at the ports '72 increases, thus building up pressure in the control chamber 76 and moving the valve 57 to the right until it reaches the position illustrated in FIGURE 2. This is the condition just prior to governing. At this time it wil be observed that any further movement of the valve to the right as will be occasioned by any further increase in engine speed will provide a connection from the power chamber 44 to the engine manifold through the ports 48 and 49 and the passage formed by the recess 6:? in the valve :37. When this occurs, manifold vacuum is admitted to the power chamber 44 both through he restricted orifice 53 and through the port 4-8 and hence pressure within the power chamber 44 will fall below atmospheric. Since the connecting chamber 54 remains at all times at atmospheric pressure, a pressure differential is established across the diaphragm 40 tending to move the diaphragm to the right against the spring Stl and such movement is accompanied by initial closing movement of the governor throttle plate or valve 32, as seen in FEGURE 3.

Initial closing movement of the throttle valve 32 will have the effect of restricting the flow of air through the induction passage 3% so that air flow past the ports '72 diminishes and hence the pressure within the control chamber 76 will also diminish, thus permitting a slight movement of the piston valve 57 to the left through the action of the spring 66.

In addition to reducing the velocity of air flow through the induction passage 3 repositioning of the governor throttle valve 32 to a partially closed position has the secondary effect of increasing manifold vacuum. Accordingly, a change in manifold vacuum, assuming other conditions to remain constant, will cause a further reduction in pressure in the power chamber 44. Accordingly, the construction is effective to move the governor throttle valve to the position required to maintain speed at substantially the desired speed, within a relatively small spread or range of regulation. The connecting of restricted port 53 to the air induction passage at port 53a below the pick-ups 72 results in the following after cut-off. As the governor throttle closes, the pressure below the governor throttle decreases (vacuum increases), and the pressure above the governor throttle increases (vacuum decreases).

Since the manifold vacuum increases rapidly during unloading, the movement of the valve 57 to the left would not sufliciently reduce the vacuum in chamber 44. The election of restriction 53 and adjustments, etc., will allow the vacuum in chamber :4; to attain the desired value since the vacuum decreases at port 53a a the manifold vacuum applied to port 43 by conduit 28 increases.

From the foregoing it will be observed that the position of the governor throttle valve 32 is determined by the pressure existing within the power chamber 44 which varies from substantially atmospheric pressure to a value not substantially above the existing manifold vacuum. The

instantaneous pressure existing within the power chamber 4 is determined by the restriction to air flow afforded by the bleed orifice 53, the instantaneous value of manifold vacuum, and the amount of restriction to flow provided by the valve 57. The only variable which affects the position of the valve 57 is the velocity of air flow through i the induction passage 36.

Thus, the initial closing movement of the governor throttle plate occasioned by an increase in engine speed above nominal governed speed has two results, one of which tends to produce opening movement of the governor throttle plate and the other of which tends to produce closing movement of the governor throttle plate. The reduction in velocity of air flow which accompanies partial closing of the governor throttle valve tends to produce opening movement of the governor throttle plate. The increase in manifold vacuum which accompanies closing movement of the governor throttle plate increases the vacuum in the power chamber 44 and hence tends to produce further closing movement of the governor throttle plate. By varying constants in the system it will be apparent that the net result of the two factors tending to produce opposite movement of the governor throttle plate may be controlled as desired to give the governor the required sensitivity combined with stability and low spread or regulation.

Cir

The drawings and the foregoing specification constitute a description of the improved engine speed governing means in such full, clear, concise and exact terms as to enable any person skilled in the art to practice the invention, the scope of which is indicated by the appended claims.

What I claim as my invention is:

1. A velocity governor adapted to be inserted between the engine manifold and a carburetor of an internal combustion engine, said governor comprising a generally annular body, a governor throttle valve in said body, said body having at one side thereof a projection formed with a pair of laterally facing recesses therein, a housing having a similar pair of laterally extending recesses positioned against said projection with the recesses of said projection and housing in alignment, flexible diaphragm means between said projection and housing to divide the space enclosed by said recesses into four sealed apart chambers, a conduit adapted to connect a first one of said chambers to a source of variable vacuum, a port connecting said first chamber to a second one of said chambers at the side of said first chamber, a valve movable in said first chamber operable to connect and disconnect said conduit and port, means connecting said valve to the diaphragm sealing said one chamber, means connecting a third one of said chambers at the opposite side of said diaphragm from said first chamber to the air induction passage of said body and including a port open upstream of said induction passage, the fourth one of said chambers opposite the diaphragm sealing said second chamber being open to atmosphere, resilient means in said second chamber connected to the diaphragm sealing said second chamber from said fourth chamber, and mechanical actuating means connecting said last named diaphragm to said throttle valve.

2. A velocity governor adapted to be inserted between the engine manifold and a carburetor of an internal combustion engine, said governor comprising a generally annular body, a governor throttle valve in said body, said body having at one side thereof a projection formed with a pair of laterally facing recesses therein, a housing having a similar pair of laterally extending recesses positioned against said projection with the recesses of said projection and housing in alignment, flexible diaphragm means between said projection and housing to divide the space enclosed by said recesses into a control chamber, a valve chamber in alignment with said control chamber and sealed therefrom by a first portion of said diaphragm means, a vented connecting chamber at the side of said control chamber, and a power chamber in alignment with said connecting chamber and sealed therefrom by a second portion of said diaphragm means, a control passage connecting said control chamber to the interior of said induction passage and having ports facing upstream therein, a port in the wall between said valve chamber and power chamber, a supply passage connecting said valve chamber to a source of actuating pressure, a piston valve in said valve chamber including means movable alternatively to connect said port and said supply passage and to disconnect said port and said supply passage, said valve chamber having an atmospheric vent in the end thereof remote from said first diaphragm portion, a spring in said power chamber engaging said second portion of said diaphragm means, and mechanical means extending across said connecting chamber and connected to said throttle valve.

3. A velocity governor for an internal combustion engine having an air induction passage, a governor throttle valve in said passage, a fluid pressure motor connected to said throttle valve to position the same, a supply passage adapted to connect said motor to a source of actuating vacuum, a control valve in said supply passage responsive directly to the velocity of air flowing in an unrestricted portion of said induction passage to control said motor, and a bleed passage connected between said air induction passage and said motor to cause the effectiveness of the vacuum applied thereto by the supply passage to be a function of the control valve opening in said supply passage.

4. A velocity governor for an internal combustion engine having an air induction passage, a governor throttle valve in said passage, a fluid pressure motor connected to said throttle valve to position the same, a supply passage adapted to connect said motor to a source of variable actuating vacuum, a control valve in said supply passage responsive directly to the velocity of air flowing in an unrestricted portion of said induction passage to control said motor, and a bleed passage connected between said air induction passage and said motor to cause the effectiveness of the vacuum applied thereto by the supply passage to be a function of the control valve opening in said supply passage and the value of the variable actuating vacuum existing at said source.

5. A velocity governor for an internal combustion engine comprising a carburetor having an induction passage and a carburetor throttle valve therein, said governor being adapted to be positioned between the carburetor and engine and having an induction passage to conduct fuel mixture from the carburetor to the engine, a governor throttle valve in the governor induction passage, a fluid motor connected to said governor throttle valve, a supply passage connecting said motor to a source of actuating vacuum, a restricted passage connecting said motor to the induction passage of said governor at a point upstream from said governor throttle valve, and means responsive directly to speed of fuel mixture in the induction passage of said governor for controlling the application of actuating vacuum to said motor.

6. A governor for an internal combustion engine having a carburetor and an induction manifold comprising a body, an induction passage through said body, a throttling valve in said induction passage, first pressure responsive means normally responsive only to the pressure anterior of said throttling valve, means connecting said first pressure responsive means and said throttling valve, a conduit adapted to have one end in communication with the pressure within said induction manifold, valve means controlling the communication of the other end of said conduit with said first pressure responsive means, and second pressure responsive means adapted to control the position of said valve means in accordance with the dynamic pressure within said induction passage.

7. A governor for an internal combustion engine, said governor comprising a body having an induction passage, a throttling valve in said induction passage, a pressure chamber having a movable wall connected to said throttling valve, a first motor passage means adapted to connect said chamber to a source of vacuum, second motor passage means connecting said chamber to atmosphere, control valve means in said passage means, and means responsive to air velocity in said induction passage operatively connected to said control valve means to maintain said first passage means closed and said second passage means open at air velocity below a predetermined value, said last recited means being effective to close both of said passage means at an intermediate air velocity, and to maintain said second passage means closed and to open said first passage means at a higher air velocity.

8. A governor for an internal combustion engine, said governor comprising a body having an induction passage, a throttling valve in said induction passage, a pressure chamber having a movable wall connected to said throttling valve, a first motor passage means adapted to connect said chamber to a source of vacuum, second motor passage means connecting said chamber to atmosphere, control valve means in said passage means, means responsive to air velocity in said induction passage operatively connected to said control valve means to maintain said first passage means closed and said second passage means open at air velocity below a predetermined value, and a restricted passage connecting said chamber to said induction passage anterior to said throttling valve.

9. In an internal combustion engine, governor mechanism comprising a mixture intake passage, an operator controlled throttle valve in said passage, a governor throttle valve in said passage downstream from said operator controlled throttle valve, a fluid operated throttle valve motor including an expansible chamber having a movable wall connected to said governor throttle valve, restricted passage means connecting said chamber to said intake passage intermediate said throttle valves, said chamber having a vacuum port for connection to a vacuum source and an atmospheric port for connection to atmosphere, valve means movable to control said ports, a fluid operated valve motor including a chamber having a movable wall connected to said valve means, and means to supply said last named chamber with fluid under a pressure which is dependent directly on the velocity of flow of mixture in said passage at a point between said operator controlled throttle valve and said governor throttle valve.

10. In an internal combustion engine, governor mecha nism comprising a mixture intake passage, an operator controlled throttle valve in said passage, a governor throttle valve in said passage downstream from said operator controlled throttle valve, a fluid operated throttle valve motor including an expansible chamber having a movable wall connected to said governor throttle valve, a restricted fluid passage connecting the interior of said expansible chamber of said throttle valve motor to static pressure within said mixture passage at a point between said operator controlled throttle valve and said governor throttle valve, said chamber having a vacuum port for connection to a vacuum source and an atmospheric port for connection to atmosphere, valve means movable to control said ports, a fluid operated valve motor including a chamber having a movable wall connected to said valve means, and means to supply said last named chamber with fluid under a pressure which is dependent directly on the velocity of flow of mixture in said passage at a point between said operator controlled throttle valve and said governor throttle valve.

11. An internal combustion engine having a mixture intake passage, an operator controlled throttle valve in said passage, a governor controlled throttle valve in said passage, a fluid pressure actuated motor connected to said governor throttle valve to actuate the same, restricted passage means connecting said motor to said intake passage intermediate said throttle valves, a source of operating vacuum connected to said motor, and means responsive to the velocity of flow of mixture in said intake passage intermediate said throttle valves eifective to control the connection between said source of vacuum and said motor.

References Cited in the file of this patent UNITED STATES PATENTS 1,547,269 Spencer July 28, 1925 2,424,836 Mallory July 29, 1947 2,505,292 Mallory Apr. 25, 1950 2,661,728 Thorner Dec. 8, 1953 2,731,974 Krueger Jan. 24, 1956 2,887,998 Thorner May 26, 1959 

1. A VELOCITY GOVERNOR ADAPTED TO BE INSERTED BETWEEN THE ENGINE MANIFOLD AND A CARBURETOR OF AN INTERNAL COMBUSTION ENGINE, SAID GOVERNOR COMPRISING A GENERALLY ANNULAR BODY, A GOVERNOR THROTTLE VALVE IN SAID BODY, SAID BODY HAVING AT ONE SIDE THEREOF A PROJECTION FORMED WITH A PAIR OF LATERALLY FACING RECESSES THEREIN, A HOUSING HAVING A SIMILAR PAIR OF LATERALLY EXTENDING RECESSES POSITIONED AGAINST SAID PROJECTION WITH THE RECESSES OF SAID PROJECTION AND HOUSING IN ALIGNMENT, FLEXIBLE DIAPHRAGM MEANS BETWEEN SAID PROJECTION AND HOUSING TO DIVIDE THE SPACE ENCLOSED BY SAID RECESSES INTO FOUR SEALED APART CHAMBERS, A CONDUIT ADAPTED TO CONNECT A FIRST ONE OF SAID CHAMBERS TO A SOURCE OF VARIABLE VACUUM, A PORT CONNECTING SAID FIRST CHAMBER TO A SECOND ONE OF SAID CHAMBERS AT THE SIDE OF SAID FIRST CHAMBER, A VALVE MOVABLE IN SAID FIRST CHAMBER OPERABLE TO CONNECT AND DISCONNECT SAID CONDUIT AND PORT, MEANS CONNECTING SAID VALVE TO THE DIAPHRAGM SEALING SAID ONE CHAMBER, MEANS CONNECTING A THIRD ONE OF SAID CHAMBERS AT THE OPPOSITE SIDE OF SAID DIAPHRAGM FROM SAID FIRST CHAMBER TO THE AIR INDUCTION PASSAGE OF SAID BODY AND INCLUDING A PORT OPEN UPSTREAM OF SAID INDUCTION PASSAGE, THE FOURTH ONE OF SAID CHAMBERS OPPOSITE THE DIAPHRAGM SEALING SAID SECOND CHAMBER BEING OPEN TO ATMOSPHERE, RESILIENT MEANS IN SAID SECOND CHAMBER CONNECTED TO THE DIAPHRAGM SEALING SAID SECOND CHAMBER FROM SAID FOURTH CHAMBER, AND MECHANICAL ACTUATING MEANS CONNECTING SAID LAST NAMED DIAPHRAGM TO SAID THROTTLE VALVE. 